Method and device for laying-in yarn in a warp knitting machine

ABSTRACT

INTERMITTENTLY BY A DRIVE WHICH OPERATES THE SINKER BAR WITH A DIFFERENT STROKE IN DIFFERENT COURSES.   THE OPERATING SPEED OF A RASCHEL KNITTING MACHINE WITH A YARN LAYING-IN ARRANGEMENT IS INCREASED BY SPREADING THE LAPPING MOVEMENTS OF THE DEFLECTORS FOR THE LAID-IN WEFT YARN OVER THE KNITTING PERIOD OF TWO OR MORE COURSES IN THE GROUND FABRIC, THE INTERVENING COURSES BEING SKIPPED BY THE LAID-IN YARN. THE YARN DEFLECTORS ARE MOUNTED ON THE SINKKER BAR AND MOVED INTO OPERATING POSITION ONLY

- Feb. 21, 1973 K m. V 3,718,010

UE'IHOD AND DEVICE FOR LAYING'IN YARN IN A WARP KNITTING IACHINE Filed Oct. 21, 1970 s Shegts-Sheet 1 INVEN'TOR.

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G NT Feb. 27, 1973 K. KOHL ETHOD AND DEVICE FOR LAYING'IN YARN IN A WARP KNITTING ncamn 3 Sheets-Sheet 2 mod on. 2 1, 1970 F V/////V///////// [N VEN' TOR.

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Feb. 27, 1973 K. KOHL 3,718,010

METHOD AND DEVICE FOR LAYING-1N YARN IN A WARP KNITTING momma Filed Oct. 21, 1970 I5 Sheets-Sheet 3 Fig 4 2J0 ab I L L J I *W j a b c d e INVENTOR.

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United States Patent 3,718,010 METHOD AND DEVICE FOR LAYING-IN YARN IN A WARP KNITTING MACHINE Karl Kohl Chlorodontstrasse, 6053 Obertshausen bei, Offenbach am Main, Germany Filed Oct. 21, 1970, Ser. No. 82,780 Claims priority, application Germany, Oct. 21, 1969, P 19 52 810.0 Int. Cl. D04b 23/06 US. C]. 66-84 2 Claims ABSTRACT OF THE DISCLOSURE The Operating speed of a Raschel knitting machine with a yarn laying-in arrangement is increased by spreading the lapping movements of the deflectors for the laid-in weft yarn over the knitting period of two or more courses in the ground fabric, the intervening courses being skipped by the laid-in yarn. The yarn deflectors are mounted on the sinker bar and moved into operating position only intermittently by a drive which operates the sinker bar with a different stroke in different courses.

This invention relates to a method and a device on a Raschel warp knitting machine for laying-in weft yarn, and particularly to an arrangement in which yarn is laidin only in selected courses of the ground fabric of warp yarn stitches.

Known warp knitting machines with intermittently operating laying-in arrangements have relatively low output rates because the speed of the knitting implements in the machine is limited by the rate of movement of the yarn guide carrying the laid-in yarn. The length of a knitting cycle must be sufficient to provide time for the lapping movement of the yarn guide carrying the laid-in yarn, such movement extending frequently over the entire eifective width of the machine. The machine speed available under such conditions is low, and much lower than would be necessary under otherwise analogous conditions without the laying-in arrangement.

The laid-in yarn is brought near the knitting needles in the known knitting machines of this type by yarn deflectors which move toward and away from the knitting needles during each knitting cycle whether or not a yarn is to be laid-in because the yarn deflectors are connected or integral with the sinkers which need to be brought into operating position during each knitting cycle. When a course of stitches in the ground fabric is not to be provided with laid-in yarn, the yarn guide for the laid-in yarn is stopped, and is therefore provided with an intermittent drive in the known machines.

The primary object of this invention is the provision of a warp knitting machine which permits yarn to be laid only in selected courses of the ground fabric without reducing the speed of the machine and without foregoing the advantages of yarn deflectors connected with the sinkers for joint movement.

The desired mode of operation is achieved, according to this invention, by extending each lapping movement of the yarn guide carrying the laid-in yarn over the time required for knitting two or more courses of the ground fabric, the speed of yarn guide movement being related to the number of courses which are to be skipped by the laid-in yarn, the yarn deflectors being brought into operative position only in the course or courses intended to receive laid-in yarn. The machine speed is thereby made virtually independent of the time required for the lapping movement of the yarn carrier for the laid-in yarn. When alternating courses are to be skipped by the laid-in yarn, the lapping movement of the yarn carrier for the 3,718,010 Patented Feb. 27, 1973 last-mentioned yarn may extend over the knitting period of two courses in the ground fabric which is suflicient under all practical conditions to complete back-and-fourth movement of the yarn carrier along the row of knitting needles without reducing the machine speed.

The device required for such operation includes a continuously operating drive for the yarn carrier of the laying-in mechanism, and an intermittent drive for the yarn deflectors. In order to permit the yarn deflectors to be connected with the sinkers for joint movement, the length of the sinkers in their direction of movement is made suflicient to interengage the row of knitting needles even when the yarn deffectors do not move within operating range of the needles.

An embodiment of the invention is illustrated in the drawing in which:

FIG. 1 shows knitting implements of a Raschel knitting machine equipped with the laying-in arrangement of the invention in side elevation;

FIG. 2 shows the device of FIG. 1 in fragmentary front elevation;

FIG. 3 shows the sinker-bar mechanism in the machine of FIG. 1 in side elevation;

FIG. 4 is a conventional motion diagram of the sinkers of FIG. 3; and

FIG. 5 illustrates portions of the drive for the yarn guide in the device of FIG. 2.

Referring initially to FIGS. 1 and 2, there is shown only as much of an otherwise conventional Raschel warp knitting machine as is needed for an understanding of the basic features of this invention.

The yarn or weft guide 1 for the laid-in yarn, not itself seen, is guided over the full length of the needle bar (not shown) along a rail 2 and is attached to a rope 3 trained over two pulleys at the two sides of the machine. The rope 3 moves the yarn guide 1 back and forth along the rail 2 when a pinion-and-segment transmission 4 turns one of the pulleys alternatingly in two directions, the segment being oscillated continuously by a crank 5, as will be explained further with reference to FIG. 5.

The yarn deflectors 6 are integral with respective intermediate portions of the otherwise conventional sinkers 8 of the machine and move a distance 7 toward a row of knitting needles 9 when it is desired to tie the yarn sup plied by the guide 1 to the ground fabric knitted on the needles 9 in a conventonal manner not shown. The maximum stroke 7 of the yarn deflectors 6 and sinkers 8 and the length of the sinkers 8 are chosen in such a manner that only the front ends of the sinkers may be interdigitated with the needles 9 in the normal knitting cycle without the laid-in yarn being brought within range of the loops on the needles 9.

The yarn deflectors 6 travel over the full distance 7 into their operating positions only when it is desired to lay a yarn warpwise into a course of the ground fabric, and FIG. 3 shows a sinker bar mechanism which permits yarn to be laid-in into alternating courses.

The yarn deflectors 6 are mounted in the usual manner on the sinker bar 10 which oscillates about the axis of a rocker shaft 11 on supporting arm 12. The shaft 11 is connected by as many bearing brackets 13 with the machine frame 14 as are needed in view of the width of the machine.

A cam shaft 15 journaled in the frame 14 carries an eccentric cam 16 having an axial flange 17 which is engaged by trucks 18a, 18b on an arm 19 fulcrumed on a stationary shaft 20 in the frame 14. A push rod 21 transmitts the movement of the arm 19 to the arm 12 which supports the sinker bar 10.

The illustrated cam 16 is releasably mounted on the shaft 15 and may be interchanged with another cam whose shape is obvious from inspection of FIG. 4. In the diagram of FIG. 4 the horizontal position of the yarn deflectors 6 and sinkers 8 is shown as a function of the angular movement of the main drive shaft in the illustrated knitting machine, the shaft being described below with reference to FIG. 5. The cam shaft is connected to the main drive shaft by a step-down transmission in such a manner that the cam shaft 15 makes one revolution during two revolutions of the main drive shaft and the corresponding two knitting cycles 23a, 23b. With the illustrated cam 16, the sinker movements 22a, 22b in the two cycles are equal and correspond to the stroke 22 indicated in FIG. 3 which is suflicient for the normal operation of the sinkers 8, but not suflicient to bring the yarn on the guide 1 within range of the needles 9. No yarn is laid-in with the illustrated cam 16.

When it is desired to provide a laid-in yarn in every other course of the ground fabric, the cam 16 is replaced by a cam one half of which is identical with the corresponding portion of the cam 16, and causes sinker movement 22a in each alternating course 23a. In the other courses 23b of the successive pairs of courses, the sinkers move over the full distance 24 indicated in FIGS. 3 and 4, and practically identical with the distance 7 in FIG. 1.

The arrangement evident from FIG. 4 causes a yarn to be laid in in alternating courses, one course being skipped. The time available for moving the yarn guide 1 over the full Width of the machine is thus equal to theperiod of time required for two knitting cycles in the ground fabric, and the machine can operate with laid-in yarn in every other course at as high a rate as could be knitting the ground fabric only.

Additional elements of the continuous drive mechanism for the yarn guide 1 are illustrated in FIG. 5. Movement is transmitted between the main drive shaft 25 of the knitting machine and a countershaft 26 by a timing chain 27 trained over sprockets 28a, 28b on the two shafts. It will be appreciated that the cam shaft 15 and the main drive shaft 25 are connected in an analogous manner. A bevel gear 29 on the counter shaft 26 meshes with a bevel gear 30 to which one end of a connecting rod 31 is hinged. The other end of the connecting rod is pivotally fastened to the afore-mentioned crank arm 5 of the segment-and-pinion drive 4.

If it is desired to change the frequency of laid-in yarns in the ground fabric knitted on the needles 9, yet another cam is substituted for the cam 16, and the transmission ratios between the shafts 15, 25, 26 may also have to be changed in an obvious manner, not requiring more detailed description.

It should be understood, therefore, that the foregoing disclosure relates only to preferred embodiments of the invention, and that, within the scope of the appended claims, the invention may be practiced otherwise than as specifically described.

What is claimed is:

1. In a warp knitting machine having knitting implements for knitting successive pairs of consecutive courses in a fabric, said implements including (1) a plurality of knitting needles spaced in a coursewise direction over the width of said machine,

(2) a plurality of sinker elements, each sinker ele- 4 ment having a free end portion and an intermediate portion carrying a yarn deflector,

(3) sinker drive means for jointly moving said sinker elements transversely of said direction between a retracted position and an operating position of interdigitating relationship with said knitting needles during the knitting of each course, said intermediate portion of each sinker element being spaced from said free end portion in the direction of movement of the sinker element from said operating position toward said retracted position,

(4) feeding means for feeding yarns to said knitting implements, said feeding means including a weft yarn guide member, and

yarn guide drive means for moving said guide member over said width of said machine,

(5) a main drive shaft, and

(6) motion transmitting means interposed between said main drive shaft, said sinker drive means, and said yarn guide drive means for actuating said drive means in timed sequence,

the improvement which comprises:

(a) said sinker drive means including means interdigitating only front end portions of said sinker elements during the knitting of a first course of each of said pairs of courses while keeping said yarn deflectors remote from said knitting needles, and interdigitating said intermediate portions with said knitting needles during the knitting of the second course of each pair for bringing a Weft yarn fed by said guide member within range of said knitting needles by means of said yarn deflectors, and

(b) said yarn guide drive means including means moving said yarn guide member over said width in one direction over a period substantially longer than the knitting of one of said courses.

2. In a machine as set forth in claim 1, said period extending substantially over the time required for the knitting of the two courses of each of said pairs of courses.

References Cited UNITED STATES PATENTS 2,200,280 5/1940 Klumpp et al 66-85 2,247,092 6/1941 Klumpp et a1 6884 2,452,579 11/1948 Lambach 66-84 3,552,151 1/1971 Schuler et al. 66-125 1,924,649 8/1933 Morton 66--85 FOREIGN PATENTS 1,064,186 8/1959 Germany 65--84 500,223 11/1954 Italy 66-60 707,492 5/ 1941 Germany 66--86 390,485 7/ 1931 Great Britain 66-86 OTHER REFERENCES Darlington, Liba Schussomat, Knitted Outer Wear Times, Jan. 22, 1968, vol. 37, No. 4, pp. -61.

RONALD FELDBAUM, Primary Examiner 

